Piezoelectric actuator e.g. roll actuator, for fuel injection valve of e.g. diesel engine, has electrode layers and measuring electrodes provided in active and sensor parts, respectively, and extended in circumferential direction

摘要

The actuator (2) has electrode layers (15, 16) provided in an active part (17), and measuring electrodes (18, 19) provided in a sensor part (20). The electrode layers and the measuring electrodes are extended along a longitudinal axis (12) and approximately in a circumferential direction (26). A piezoceramic material (13) is formed between the electrode layers. The sensor part is arranged within or outside of the active part. The sensor part has two longitudinal sections separated along the longitudinal axis. An independent claim is also included for a fuel injection valve comprising a nozzle needle.